Casshern is set late in the 21st century. After 50 years of devastating war between Europa and the Eastern Federation, the latter has emerged victorious, and the new federation of Eurasia is formed. There can be no glorious peace, however, as the planet has been ravaged by chemical, biological and even nuclear weapons and the entire human race is dispirited and exhausted by half a century of war. A geneticist named Azuma brings hope in the form of a ‘neo-cell’, which can rejuvenate human parts with no risk of rejection. But nature interferes with science to create a new kind of menace that forces the entire human race to fight an ultimate war against its own extinction.